Spacer for grip adjustment of firearm

ABSTRACT

A spacer assembly configured for mounting between a pistol grip and a lower receiver of a weapon. The spacer assembly includes an indexer and a spacer. The indexer is configured to shift a position of the pistol grip when mounted to the lower receiver via the indexer. The shifted position of the pistol grip shifts the pistol grip rearward away from a trigger of the lower receiver a distance, such that a trigger indexing is selected for a user. The spacer is configured to couple to the indexer to provide for a smooth transition between the pistol grip and the lower receiver. The indexer includes an upper portion configured to mount to a pistol grip attachment point of the lower receiver. The indexer also includes a lower portion configured to receive the pistol grip. The lower portion mimics the pistol grip attachment point of the lower receiver.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the filing benefits of U.S. provisional application, Ser. No. 62/856,277, filed Jun. 3, 2019, which is hereby incorporated by reference herein in its entirety.

FIELD OF THE INVENTION

The present invention is directed to firearms, and in particular to firearms with pistol grips.

BACKGROUND OF THE INVENTION

Conventional semi-automatic rifles, such as the popular AR-10/AR-15 type rifles (which are based on the original ArmaLite AR-10/AR-15 designs), as well as other semi-automatic or bolt action rifles, often include a pistol grip positioned with respect to the rifle's trigger. The pistol grip is mechanically coupled to a portion of the rifle that typically houses a trigger group and a fire control group. In such AR-10/AR-15 type rifles (as well as a pistol version), this portion of the rifle (to which the pistol grip attaches) is referred to as the “lower receiver.” In addition to the pistol grip, the lower receiver contains and/or receives a trigger/fire control group and a magazine well for receiving magazines, as well as other parts. When combined with an “upper receiver,” the lower receiver/upper receiver combination houses and/or serves as attachment points for the rest of the components of the typical AR-10/AR-15 type rifle.

SUMMARY OF THE INVENTION

An exemplary spacer assembly of the present invention is configured for mounting between a pistol grip and a pistol grip attachment point of a weapon's lower receiver. The spacer assembly includes an indexer configured to shift the installation position of the pistol grip. When the indexer is mounted to a lower receiver, a pistol grip subsequently mounted to the lower receiver will be repositioned a selected distance back from a trigger of the lower receiver. Such movement of the pistol grip back from the trigger provides for optimal trigger indexing that is selected for a particular user. The spacer assembly further includes a spacer configured to couple to the indexer, and once coupled, to provide an ergonomic fit between the repositioned pistol grip and the lower receiver. The indexer comprises an upper portion that is configured to mount the indexer to the pistol grip attachment point. The indexer further comprises a lower portion that is configured to receive a pistol grip.

An exemplary spacer assembly of the present invention is configured for mounting between a pistol grip and a lower receiver of a weapon. The spacer assembly includes an indexer and a spacer. The indexer is configured to shift a position of the pistol grip when mounted to the lower receiver via the indexer. The shifted position of the pistol grip shifts the pistol grip rearward away from a trigger of the lower receiver a distance, such that a trigger indexing is selected for a user. The spacer is configured to couple to the indexer to provide for a smooth transition between the pistol grip and the lower receiver. The indexer includes an upper portion configured to mount to a pistol grip attachment point of the lower receiver. The indexer also includes a lower portion configured to receive the pistol grip. The lower portion mimics the pistol grip attachment point of the lower receiver.

In an aspect of the present invention, the indexer is configured to shift the pistol grip a selected distance rearward to provide a selected trigger indexing for a selected hand size and/or selected hand physical dimension.

In another aspect of the present invention, the spacer is configured in one of a plurality of different thickness and shapes, and wherein a particular thickness and shape is selected to provide a particular ergonomic fit between the pistol grip and lower receiver for a selected hand size and/or selected hand physical dimension.

In yet another aspect of the present invention, the indexer is optionally equipped with a cavity and threaded opening for receiving and securing a thumb rest.

In a further aspect of the present invention, the indexer is formed of at least one of aluminum, reinforced polymeric material, and wherein the spacer is formed of at least one of aluminum, and reinforced polymeric material.

In an aspect of the present invention, the spacer is coupled to the indexer via an attachment feature on an underside of the spacer. The attachment feature is configured to couple to the indexer on the upper portion of the indexer. The attachment feature may be configured to be at least partially inserted into an opening on the upper portion of the indexer.

In another aspect of the present invention, the attachment feature is at least one prong that is configured to friction fit in at least one opening on the upper portion of the indexer.

Therefore, the present invention provides for a spacer assembly configured to reposition a pistol grip a selected distance back from a trigger of a lower receiver when the spacer assembly is mounted between the pistol grip and the lower receiver. Such movement of the pistol grip back from the trigger provides for optimal trigger indexing that is selected for a particular user.

These and other objects, advantages, purposes and features of the present invention will become apparent upon review of the following specification in conjunction with the drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a right-side view of a pistol grip installed on a lower receiver of a weapon;

FIG. 2 is a right-side exploded view of a spacer assembly positioned between a pistol grip and a lower receiver of a weapon in accordance with an embodiment of the present invention;

FIG. 3 is a left-side perspective view of the spacer assembly, pistol grip, and lower receiver of FIG. 2;

FIG. 4 is a right-side view of the spacer assembly of FIG. 2 positioned between the pistol grip and lower receiver in accordance with an embodiment of the present invention;

FIG. 5 is a right-side view of the spacer assembly of FIG. 2 in accordance with an embodiment of the present invention;

FIG. 6A is a right-side perspective view of the spacer assembly of FIG. 2;

FIG. 6B is a right-side perspective view of the underside of the spacer assembly of FIG. 2;

FIG. 6C is a front-side perspective view of the spacer assembly of FIG. 2;

FIG. 7 is a right-side view of the indexer of the spacer assembly of FIG. 2 in accordance with an embodiment of the present invention;

FIG. 8A is a right-side perspective view of the indexer of FIG. 7;

FIG. 8B is a top-side perspective view of the indexer of FIG. 7;

FIG. 8C is a bottom-side perspective view of the indexer of FIG. 7;

FIG. 8D is a front-side perspective view of the indexer of FIG. 7;

FIG. 8E is a right-side perspective view of the underside of the indexer of FIG. 7;

FIGS. 9A and 9B are perspective views of the spacer of FIG. 6A in accordance with an embodiment of the present invention;

FIG. 10 is a right-side exploded view of the spacer assembly of FIG. 2 positioned between a pistol grip and a lower receiver, and further illustrating mounting bolts for securing the spacer assembly to the lower receiver and the pistol grip to the spacer assembly in accordance with an embodiment of the present invention;

FIG. 11 is a right-side view of an alternative spacer assembly positioned between the pistol grip and lower receiver of FIG. 4 in accordance with an embodiment of the present invention; and

FIGS. 12A, 12B, and 12B are perspective views of the indexer of FIG. 7 illustrating the installation of a thumb rest via an optional cavity in the indexer.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings and the illustrative embodiments depicted therein, a pistol grip 102 mechanically coupled to a lower receiver 104 is illustrated in FIG. 1. The lower receiver 104 of FIG. 1 is typically paired with an upper receiver, which when mated, together they house and/or serve as attachment points for the rest of the components of a typical rifle, such as the AR-10/AR-15 type rifle. The upper and lower receivers of the AR platform are also found in other arrangements, such as AR-type pistol configurations. Furthermore, some other rifles, such as some bolt action rifles, and rifle chassis systems also have a grip installing interface that is similar to the pistol grip attachment point discussed herein. Such embodiments would also benefit from the spacer assembly discussed herein.

FIG. 1 illustrates the pistol grip 102 conventionally coupled to a pistol grip attachment point 106 of the lower receiver 104. The pistol grip 102 is typically secured to the lower receiver 104 at the pistol grip attachment point 106 with a bolt that is inserted into the bottom of the pistol grip and into a threaded hole at the pistol grip attachment point 106. This conventional arrangement sets a distance to the trigger 108 for a user when griping the pistol grip 102 and placing their trigger finger into position at the trigger 108. This set distance can make it difficult for users with long fingers to properly “index,” or position, their trigger finger at the trigger 108. As is known in the art, a trigger finger is properly indexed or positioned when it is positioned at the trigger 108 to reliably retract the trigger 108 for firing without jerking the weapon side-to-side. A properly indexed trigger finger may also refer to the position of the trigger finger alongside, but not within the space defined by the trigger guard 110.

FIG. 2 illustrates an exploded view of a spacer assembly 200 positioned between a pistol grip 102 and a lower receiver 104. An exemplary spacer assembly 200 is configured to shift the position of the pistol grip 102 rearward with respect to the trigger 108 such that when grasp by a user, the user's trigger finger will be more comfortably indexed or positioned with respect to the trigger 108 or the area around the trigger 108 defined by the trigger guard 110. FIG. 3 illustrates a left-side perspective view of the spacer assembly 200, pistol grip 102, and lower receiver 104 of FIG. 2. As illustrated in FIGS. 2 and 3, the spacer assembly 200 includes an indexer 202 and a spacer 204. The indexer 202 is configured to couple/mate with the pistol grip attachment point 106, with the pistol grip 102 mating/coupling with the indexer 202. The indexer 202 is configured such that an indexer mounting bolt 205, illustrated in FIG. 10, passes through an opening 206 in the indexer 202 (see for example, FIG. 8E) and enters a threaded hole at the pistol grip attachment point 106 of the lower receiver 104. An exemplary indexer mounting bolt 205 is a ¼-28×¾ inch low-head-height bolt. As also illustrated in FIG. 10, the pistol grip 102 is mounted to the mounted indexer 202 via a pistol grip mounting bolt 207 that threads into a threaded hole 216 in the mounted indexer 202 (see FIG. 8E). An exemplary pistol grip mounting bolt 207 is a conventional ¼-28×½ inch bolt. The opening 206 and the threaded hole 216 are also illustrated in FIGS. 6B, 6C, 8B, 8C, and 8D.

As illustrated in FIG. 4, when the spacer assembly 200 is positioned between the pistol grip 102 and the lower receiver 104, the position of the pistol grip 102 with respect to the trigger 108 is adjusted such that the distance from the pistol grip 102, when gripped by a user, has been increased. In one embodiment, this distance is adjustable. That is, an indexer 202 with a particular length may be selected for use such that a selected distance from the pistol grip 102 to the trigger 108 is achieved. By shifting the position of the pistol grip 102 back away from the trigger area, a user's trigger finger may more easily be indexed or positioned at the trigger 108 or trigger area defined by the trigger guard 110. As also illustrated in FIG. 4, while the indexer 202 repositions the pistol grip 102 with respect to the trigger 108, the spacer 204 provides for an ergonomic fit for the user's hand when gripping the pistol grip 102. The spacer 204 provides a similar ergonomic relationship between the pistol grip 102 and the lower receiver 104 that is seen in the conventional arrangement of pistol grip 102 and lower receiver 104 (see FIG. 1).

FIG. 5 illustrates a right-side view of an exemplary spacer assembly 200 that includes an indexer 202 configured for mating with the pistol grip attachment point 106 of the lower receiver 104. The spacer assembly 200 also includes a spacer 204 that is configured to provide an ergonomic fit between the repositioned pistol grip 102 and the lower receiver 104. As also illustrated in FIG. 5, and discussed herein, the indexer 202 includes a top portion 208 that is configured to mate with the pistol grip attachment point 106, while a bottom portion 210 is configured such that the pistol grip 102 may mate with the indexer 202. As illustrated in FIGS. 8A, 8B, and 8D, openings 212 in the indexer 202 are configured to receive an attachment feature 214 on the underside of the spacer 204, such as illustrated in FIG. 9B. In one embodiment, the attachment feature 214 is a pair of prongs that form a friction fit within the openings 212 of the indexer 202. The contact between the attachment feature 214 and the openings 212 is also illustrated in FIG. 5, where the attachment feature 214 is highlighted. This attachment feature 214 is configured to position or index the spacer 204 with respect to the indexer 202. As illustrated in FIGS. 5, 6B, 9B, once positioned/indexed upon the indexer 202, the spacer 204 is retained upon the indexer 202 via a spacer retaining bolt that passes through an opening 218 in the indexer 202 to enter and engage with threads of a threaded hole 220 in the spacer 204. The spacer 204 may include a copper insert nut (220) molded into it and configured to receive and retain a #4-40×⅜ inch machine screw/bolt (the spacer retaining bolt).

FIGS. 6A, 6B, and 6C provide perspective views of an exemplary spacer assembly 200. FIG. 6A is a right-side perspective view of the space assembly 200; FIG. 6B is a right-side perspective view of an underside of the spacer assembly; while FIG. 6C is a front-side perspective view of the spacer assembly 200. FIGS. 6A and 6C provide views of the top portion 208 that is configured to mate with the pistol grip attachment point 106. That is, the top portion 208 of the indexer 202 includes a channel through which an opening 206 is provided for passage of the mounting bolt for securing the pistol grip 102 to the lower receiver 104. FIGS. 6A and 6B provide views of the bottom portion 210 that is configured for receiving the pistol grip 102. That is, the bottom portion 210 is configured to mimic or mirror the pistol grip attachment point 106 of the lower receiver 102. FIGS. 6A-6C also illustrate the placement and arrangement of the spacer 204 upon the indexer 202. As illustrated in FIG. 4, the spacer 204 is configured to provide an ergonomic fit of the pistol grip 102, when repositioned with the indexer 202.

FIG. 7 illustrates a right-side view of an exemplary indexer 202 without a spacer 204 attached thereto. As illustrated in FIG. 7, and discussed herein, the indexer 202 is configured for mating with the pistol grip attachment point 106 of the lower receiver. As also discussed herein, indexer 202 of FIG. 7 includes a top portion 208 that is configured to mate with the pistol grip attachment point 106, while a bottom portion 210 is configured such that the pistol grip 102 may mate with the indexer 202.

FIGS. 8A, 8B, 8C, 8D, and 8E provide perspective views of an exemplary indexer 202. FIG. 8A is a right-side perspective view of the indexer 202; FIG. 8B is a top-side perspective view of the indexer 202, FIG. 8C is a bottom-side perspective view of the indexer 202, FIG. 8D is a front-side perspective view of the indexer 202, while FIG. 8E is a right-side perspective view of the underside of the indexer 202. FIGS. 8A, 8B, and 8D provide views of the top portion 208 that is configured to mate with the pistol grip attachment point 106. These views are similar to those illustrated in FIGS. 6A and 6C. That is, FIGS. 8A, 8B, and 8D illustrate that the top portion 208 of the indexer 202 includes a channel through which an opening 206 is provided for passage of the mounting bolt for securing the pistol grip 102 to the lower receiver 104. Similar to FIGS. 6A and 6B, FIGS. 8C and 8E provide views of the bottom portion 210, which is configured for receiving the pistol grip. As in FIGS. 6A and 6B, the bottom portion 210 illustrated in FIGS. 8C and 8E is configured to mimic or mirror the pistol grip attachment point 106 of the lower receiver 102.

FIGS. 9A and 8B provide perspective views of an exemplary spacer 204, while FIG. 11 provides a side-view of an alternative spacer 204 a. Each spacer 204, 204 a is configured to provide an ergonomic fit between the repositioned pistol grip 102 and the lower receiver 104. Optionally, the spacer 204 may have several different embodiments that may be swapped out and mounted to the indexer 202 such that a user may select a particular spacer 204 to match with a particular indexer 202 to provide for a desired index or position of a particular user's trigger finger with respect to the trigger 108 or the trigger area defined by the trigger guard 110. For example, the spacer 204 may be configured with a particular shape to the back of the spacer 204 (see the spacer 204 a of FIG. 11 as compared to the spacer 204 of FIG. 4), or the spacer 204 may be configured with a selected thickness such that the selected spacer 204 is adapted to the user's particular hand size or physical dimensions to provide for an improved ergonomic fit for the user.

FIGS. 12A, 12B, and 12C provide perspective views of an exemplary thumb rest 230 installed on the right side of an indexer 202 a. As illustrated in FIGS. 12A-12C, the thumb rest 230 is installed onto the indexer 202 a via a recess 234 in the right side of the alternative indexer 202 a. The thumb rest 230 is secured to the indexer 202 a with a threaded bolt via threaded holes 232, 236 in the thumb rest 230 and indexer 202 a, respectively. Note that the recess 234 in the alternative indexer 202 a may be placed on the left hand side as well. Such would allow the thumb rest 230 to be configured for right-handed or left-handed users. Optionally, the thumb rest 230 may be configured to a variety of alternative arrangements for a selected size and angle of the thumb rest 230. When a thumb rest 230 is not installed, an optional spacer may be used to file the cavity 234 in the indexer 202 a. In another alternative embodiment, the indexer 202 a may include a cavity 234 on each side of the indexer 202 a, such that a thumb rest 230 may be installed on a selected side of the indexer 202 a and a spacer on the opposite side.

Special accessories which serve as alternatives to conventional pistol grips may also be configured to attach to the pistol grip attachment point 106. Such pistol grip alternatives include “fin grip” configurations that attach to the pistol grip attachment point 106 in a similar fashion.

Therefore, as discussed herein, embodiments of the spacer assembly 200 are configured to shift the position of the pistol grip 102 rearward with respect to the trigger 108, such that when grasped by a user, the user's trigger finger will be more comfortably indexed or positioned with respect to the trigger 108 or the area around the trigger 108 defined by the trigger guard 110. The spacer 204 of the spacer assembly is configured to provide an ergonomic fit between the repositioned pistol grip 102 and the lower receiver 104. As also discussed herein, the dimensions of the indexer 202 may be selected for a desired distance from the trigger 108. Similarly, the dimensions of the spacer 204 may be selected for a desired ergonomic fit depending on a user's hand size and/or physical dimension.

While the foregoing description describes several embodiments of the present invention, it will be understood by those skilled in the art that variations and modifications to these embodiments may be made without departing from the spirit and scope of the invention, as defined in the claims below. The present invention encompasses all combinations of various embodiments or aspects of the invention described herein. It is understood that any and all embodiments of the present invention may be taken in conjunction with any other embodiment to describe additional embodiments of the present invention. Furthermore, any elements of an embodiment may be combined with any and all other elements of any of the embodiments to describe additional embodiments. Changes and modifications in the specifically-described embodiments may be carried out without departing from the principles of the present invention, which is intended to be limited only by the scope of the appended claims as interpreted according to the principles of patent law including the doctrine of equivalents. 

1. A spacer assembly configured for mounting between a pistol grip and a lower receiver of a weapon, the spacer assembly comprising: an indexer configured to shift a position of the pistol grip when mounted to the lower receiver via the indexer, wherein the indexer is configured to shift the position of the pistol grip rearward away from a trigger of the lower receiver a distance, such that a trigger indexing is adjusted for a user; and a spacer configured to couple to the indexer to provide for a smooth transition between the pistol grip and the lower receiver; wherein the indexer comprises an upper portion configured to mount to a pistol grip attachment point of the lower receiver; and wherein the indexer further comprises a lower portion configured to receive the pistol grip, and wherein the lower portion mimics the pistol grip attachment point of the lower receiver.
 2. The spacer assembly of claim 1 further comprising a thumb rest secured to a side of the indexer.
 3. The spacer assembly of claim 2, wherein the thumb rest is configured with one of a plurality of angles with respect to the indexer and further configured with a selected length, width, and thickness.
 4. The spacer assembly of claim 1, wherein the indexer is configured to shift the pistol grip a selected distance rearward to provide a selected trigger indexing for a selected hand size and/or selected hand physical dimension.
 5. The spacer assembly of claim 1, wherein the spacer is further configured in one of a plurality of different thicknesses and shapes, and wherein a particular thickness and shape is selected to provide a particular ergonomic fit between the pistol grip and lower receiver for a selected hand size and/or selected hand physical dimension.
 6. The spacer assembly of claim 5, wherein the spacer comprises a concave outer surface on a side opposite the trigger.
 7. The spacer assembly of claim 1, wherein the indexer is formed of at least one of aluminum and reinforced polymeric material, and wherein the spacer is formed of at least one of aluminum and reinforced polymeric material.
 8. The spacer assembly of claim 1, wherein the spacer is coupled to the indexer via an attachment feature on an underside of the spacer, and wherein the attachment feature is configured to couple to the indexer on the upper portion of the indexer.
 9. The spacer assembly of claim 8 wherein the attachment feature is configured to be at least partially inserted into an opening on the upper portion of the indexer.
 10. The spacer assembly of claim 8, wherein the attachment feature is at least one prong that is configured to friction fit in at least one opening on the upper portion of the indexer.
 11. A method for adjusting a position of a pistol grip coupled to a lower receiver of a weapon with respect to a trigger of the lower receiver, wherein the method comprises: removing the pistol grip from the lower receiver of the weapon; installing a spacer assembly to the lower receiver, wherein the spacer assembly comprises an indexer and a spacer; wherein the indexer is configured to shift a position of the pistol grip when mounted to the lower receiver via the indexer; wherein the spacer is coupled to the indexer to provide for a smooth transition between the pistol grip and the lower receiver; wherein the indexer comprises an upper portion configured to mount to a pistol grip attachment point of the lower receiver, wherein the indexer further comprises a lower portion configured to receive the pistol grip, and wherein the lower portion mimics the pistol grip attachment point of the lower receiver; and mounting the pistol grip to the lower portion of the indexer, wherein a shifted position of the pistol grip shifts the pistol grip rearward away from the trigger of the lower receiver a distance, such that a trigger indexing is selected for a user.
 12. The method of claim 11 further comprising installing a thumb rest on the indexer by securing the thumb rest to a side of the indexer.
 13. The method of claim 12, wherein the thumb rest is positioned at one of a plurality of angles with respect to the indexer, and wherein the thumb rest comprises a selected length, width, and thickness.
 14. The method of claim 11, wherein the indexer is configured to shift the pistol grip a selected distance rearward to provide a selected trigger indexing for a selected hand size and/or selected hand physical dimension.
 15. The method of claim 11, wherein the spacer is further configured in one of a plurality of different thicknesses and shapes, wherein a particular thickness and shape is selected to provide a particular ergonomic fit between the pistol grip and the lower receiver for a selected hand size and/or selected hand physical dimension, and wherein the spacer comprises a concave outer surface on a side opposite the trigger.
 16. The method of claim 11 further comprising forming the indexer of at least one of aluminum and reinforced polymeric material.
 17. The method of claim 11 further comprising forming the spacer of at least one of aluminum and reinforced polymeric material.
 18. The method of claim 11 further comprising coupling the spacer to the indexer via an attachment feature on an underside of the spacer, wherein the attachment feature couples to the indexer on the upper portion of the indexer.
 19. The method of claim 18, wherein the attachment feature at least partially inserts into an opening on the upper portion of the indexer.
 20. The method of claim 19, wherein the attachment feature is at least one prong that is configured to friction fit in at least one opening on the upper portion of the indexer. 